This document relates to laser surgery techniques, apparatus and systems, including laser surgery techniques, apparatus and systems based on photodisruption caused by laser pulses in a tissue.
Laser light can be used to perform various surgical operations in eyes and other tissues in humans and animals. Recent development of laser surgical methods for performing operations on the human eye, such as LASIK combined with flap creation using a femtosecond laser, demonstrates that surgery of the human eye with lasers often requires precision and speed which cannot be achieved by manual and mechanical surgical methods. In laser surgery such as laser ophthalmic surgery, laser pulses interact with a target tissue to cause one or more desired surgical effects in the tissue. One example of surgical effects is the laser-induced photodisruption, a nonlinear optical interaction between light and a tissue that causes the tissue to ionize. Laser-induced photodisruption can be used to selectively remove or disrupt tissue in various surgical procedures, such as laser surgery in opthalmology. Traditional ophthalmic photodisruptors have used relatively long pulse duration lasers in single shot or burst modes involving a series of approximately a few laser pulses (e.g., three) from a pulsed laser such as a pulsed Nd:YAG laser. Newer laser surgical systems including laser ophthalmic systems tend to operate with short laser pulses with high repetition rates, e.g., thousands of shots per second and relatively low energy per pulse.
One technical challenge associated with surgical lasers of short laser pulses with high repetition rates is precise control and aiming of the laser pulses, e.g., the beam position and beam focusing of the pulses in a surgical laser beam.